The purpose of this Core is to prepare human CD34+ progenitor cells for use in Projects 4, 5, 6 and 7 which all have a requirement for studying gene transfer and expression in such cells. Since the CD34+ cells will ultimately be used in clinical protocols, the Core will include facilities for preparing the cells to meet the peripheral blood and from cord blood, to meet the varying requirements for each project. We will also have the facilities to prepare purified sub-populations of CD34+ progenitor cells from all of these sourses using a newly installed GMP cell sorter facility.